Shoe and method for making the same



July 1o, 1951 o. N. Fousf SHOE AND METHOD FOR MAKING THE SAME 2 Sheets-Sheet l Filed Nov. 19, 1948 f77/verdor rUL'Ze N FOLLS July 10, 1951 o. N. FousT 2,559,609

SHOE AND METHOD FOR MAKING THE SAME Filed Nov. 19, 1948 2 Sheets-Sheet 2 Inventor Patented July l0, 1951 SHOE AND METHOD FOR MAKING THE SAME Orville N. Foust,

Melrose, Mass., assigner to United Shoe Machinery Corporation,

Flemington, N. J., a corporation of New Jersey Application November 19, 1948, Serial No. 60,920

This invention relates to improvements in shoes. as well as to novel methods for making shoes, and more particularly to shoes and methods utilizing plastic materials.

If a shoe is to be comfortable to the wearer. the insole should lie smoothly within the shoe, should not unduly deteriorate with use and no ridges or depressions should appear because of irregularities in the substance between the insole and the outsole or because of unfilled or partially filled cavities in the shoe bottom structure which would tend to produce the above-mentioned undesired ridges or depressions during the wearing of the shoe. If a preformed insert is placed in position to ll a cavity as bounded by the overlasted margin of an upper, in most cases the cavity will not be properly filled. Shoes are not made in such a way as to form cavities which are predetermined in shape and size. The tension exerted on the uppers in lasting. the lasting margin allowance, the quality of the materials used. and other factors enter in to vary and render irregular the cavities formed in shoe bottoms. The use of a spatula to fill each cavity with a cork and resin composition is common, but lack of care in applying the composition will result in an improperly lled cavity. Moreover, that method of lling a shoe bottom is not conducive to orderliness and the shoe bottom structure is not well integrated. A perfect fit of a iiller portion within a shoe bottom has been attempted by making a separate core from the bottom of each shoe and molding an outsole to be subsequently attached to that particular shoe. Such a shoe is disclosed in the United StatesfLetters Patent No. 1,519,624, granted December 16, 1924, in the name of M. G. Munoz. The making of a special core and mold for each shoe as taught in the patent, has obvious disadvantages.

Plastic materials, in general, are impervious to air or moisture and for other reasons as well they have not been used as extensively in the manufacture of shoes as would be expected. It is possible. however, to make integrated plastic material which is micro-porous in structure. One form of such material is disclosed in the United States Letters Patent No. 2,371,868 granted in the names of Berg and Doriat on March 20, 1945. The use of micro-porous synthetic resinous polymeric material, broadly considered, is also disclosed in the applications for United States Letters Patent Serial No. 792,796, filed December 19, 1947, in the names of Foust and Ginty, now abandoned and Serial No. 41,726, led July 30, 1948 in the names of Foust and Seems. An im- 3 Claims. (Cl. 36-19.5)

2 proved and well integrated shoe bottom structure is possible because of the peculiar characteristics of the material as will further appear.

An object of the present invention is to provide a shoe with a well integrated shoe bottom structure having no cavities and utilizing sheet material, the necessary variation in dimensions of which need not be predetermined prior to assembly.

A further object of the invention is to provide a method for making the improved shoe by taking advantage of the characteristics peculiar to micro-porous synthetic resinous thermoplastic polymeric material.

To these ends, a shoe upper is preferably ilat lastedthat is-the marginal portion of an upper is fastened to and'in parallel relation with an inner sole member which is preferably lami-l nated-i. e.-provided with an outwardly facing lamina of micro-porous synthetic resinous thermoplastic polymeric material. An outer sole member. also provided with a lamina of microporous synthetic resinous thermoplastic polymerio material is then pressed on, elevated temperature, to the shoe bottom with the marginal portion of the upper con-lined between the two juxtapositioned plastic laminae. The pressure is applied to the outside of the soled shoe so as to cause the plastic material, of one lamina or preferably of the two laminae, to be compressed locally and ll the shoe bottom cavity l as bounded by the marginal portion of the upper. The parts are permanently attached together by some suitable means and for this purpose an adhesive is preferred.

The term micro-porous is used herein to de- A fine a material having pores which are so small that they are not easily discernible by the naked eye, but which permit the passage of air therethrough. The material is formed of granular particles of synthetic resinous thermoplastic polymeric material so joined together as to define small interstices or pores between them. This structure permits breathing in wear o! a shoe and provides for `adequate dissipation of moisture.

'I'he above and important features and advantages will now be discussed by reference'to the drawings and pointed out in the claims.

In the drawings.

Fig. 1 is a perspective view partially broken away of a laminated insole, the parts being assembled for use in accordance with the teachings of the present invention;

Fig. 2 is an exploded view in perspective o! a at a slightly lasted shoe and a shoe bottom, the latter being made in a manner similar to that used in making the insole of Fig. 1 and a part of the outsole-being broken away to show the construction;

Fig. 3 is a cross section of the forepart of the shoe shown in Fig. 2, an insole as shown in Fig. l forming part of the assembly;

Fig, 4 is a perspective view partially broken away of an outsole assembled for use in accordance with the teachings of the present invention; and

Fig.v 5 is a cross section of the forepart of a shoe using a conventional insole together with an outsole as shown in Fig. 4.

The micro-porous plastic material referred to above and as utilized in carrying out the present invention is provided in sheet form of uniform thickness and examples of its manufacture follow:

Example I Seventy-five parts by weight of Hycar ORF-25 latex is added to 300 parts, by weight, of water and to this is added 200 parts, by weight, of Saran F120 resin (1000 C. P. S.) powder with stirring. The stirring is continuedkwith the addition of a solution causing precipitation of the resins. 'I'his solution consists of 600 parts, by weight, of an aqueous calcium chloride solution (1% or 2% concentration) After precipitation has occurred, the water is decanted and the precipitate is centrifuged and dried at about 50 C. Subsequent to the removal of the water the somewhat loose resin particle precipitate is crumbled and sfted through a 30-mesh screen.

The resultant mixture of resins is then formed into a layer about .400 of an inch deep. Pressure is then applied to reduce the thickness of the layer to about .200 of an inch. The press platens are then heated to raise the temperature of the layer to about 118 C. About 3 minutes are used in thus heating the plastic material and after cooling, the layer of plastic particles is removed from the mold as an integrated micro-porous sheet.

The Saran F120 resin (1000 C. P. S.) powder is a copolymer of vinylidene chloride and acrylonitrile and is a product of the Dow Chemical Company of Midland, Michigan.

The Hycar OR-25 latex is a suspension of minute particles of butadiene-acrylonitrile (33%) copolymer resin suspended in a. water emulsion of a fatty acid soap. The solids content of the latex is about 40%. It is a product of the B. F. Goodrich Chemical Company, Cleveland, Ohio. A

Example II The procedure of Example I is carried out using a different resinous composition.

The powder used is composed of a thermoplastic resin as well as a thermosetting resin. parts by weight of a thermoplastic resin (95% vinyl chloride and 5% vinyl acetate) are mixed with 3 parts of a thermosetting phenol-formaldehyde resin having a softening point range of from 40 to 60 C. and a melting point range of from '70 to 75 C. (a resin of the latterl type is called Durez #12687 and is produced by Durez Plastics 8a Chemicals, Inc. of North Tonawanda, New York).

The plasticizer used is composed of 5 parts of dimethoxy ethyl phthalate.

An integrated micro-porous sheet results from the sintering operation.

Example III Sixty-three parts by weight of Hycar OR-15 latex is added to 300 parts by weight of water and to this is added 134 parts by Weight of Saran latex F122 (both are defined below) with stirring. Precipitation of the resins is brought about by addition of a solution of calcium chloride as in Example I. After precipitation has occurred the water is decanted and the precipitate is centrifuged and dried at about 50 C.

After sifting through a BO-mesh screen, the resultant mixture of resins isformed into a layer about .235 of an inch deep. Pressure is then applied to reduce the depth of the layer to .125 of an inch while the temperature of the material is raised to 118 C. After cooling the layer of sintered material is removed as an integral whole.

The sheet is then dipped in a plasticizer composed of a solution of 828 parts of lcarbon tetrachloride, 92 parts of Paraplex G50 and 92 parts of Santicizer B16. The excessive plasticizer is drained from the sheet after which the sheet is dried by heating it for a time to 60 C. The temperature of the sheet is then raised to C. for flve minutes.

The Hycar OR-l5 latex is an oil resistant butadiene-acrylonitrile copolymer with about 40 per cent total solids content and is made by the B. F. Goodrich Chemical Company.

The Saran latex F122 is an unplasticized latex with a total solids content of about 58 per cent by weight. It is a copolymer of vinylidene chloride and acrylonitrile suspended in water containing dispersing and stabilizing agents. It is a product of The Dow Chemical Company.

Paraplex G50 is used as a resinous plasticizer and is a low-viscosity polyester resin. It is a product of The Resinous Products Division of the Rohm & Haas Company, Philadelphia, Pennsylvania. It is stable and does not migrate vto any appreciable extent.

The Santicizer B16 is a product of Monsanto Chemical Company, St. Louis, Missouri, and is f added strength and toughness.

Example IV The procedure of Example III is carried out but with the use of a vulcanizing agent.

The powder used is composed of 670 parts by Weight of Saran F122 latex, 315 parts by weight of Hycar OR-25 latex, 3.4 parts by weight of dispersed Ethyl Zimate and 2.6 parts by weight of dispersed sulphur.

The Ethyl Zimate is a rubber accelerator produced by the R. T. Vanderbilt Company, New York, New York and, together with the sulphur, acts to bring about vulcanization.

The particles of resin are precipitated out of a solution as in Example III and the sintered sheet is post plasticized, drained, and heated as in Example III.

The micro-porous sheet is excellent for the purpose at hand.

- In carrying out the present invention, an inner tion- 2l of the upper inthe in place o I is made or cut with the proper contour to iit the bottom of a shoe last Ilv (Fig. 2).

T he insole III is then temporarily attached by some means such as tacks to the last I8 with the 'plastic lamina I4 facing outwardly. The shoe upper isthen assembled on the last Il and 44-tiie usual pulling-over, side, toe and -heel seat lasting operations performed. The marginal porlasting operations is preferably secured to the insoleA l0 by curved staples 22 along the sides. by cement at the toe end and -by tacks 24 around the heel seat portionof the shoe. A shank piece 26 is then tacked in place upon the insole I0. vAdhesives may be used the tacks 24 and staples 22 or may be supplem ntal thereto for holding the overlasted upper marginal portion 2l in place. In

cement toe lasting, tacks may be temporarily,

holes :o in the cverlasd 6 cavity. The lasting -operation causes the shoe upper margin 28 to sink slightly into the plastic lamina Il of the insole ill and the sole attaching operation causes the plastic material of the lamina u 4to complete the filling of the'sho'e bottom cavity.- The porosity of the plastic material is necessarily and substantially reduced where the material is contacted by the margin 28 because of the heat and pressure. The resilience and porosity-of'other portions of the plastic material need not be affected, however, anddsuch portions serve admirably as a illler.-

The shoe. as shown in Figs. 2 and 3, presents a vsmooth interior surface to the foot of the wearer and there are no shoe bottom cavities tocause any irregularities during wear. The use of conventional cork and resin compositions for'illling the bottom is dispensed with and the plastic material of the outsole lamina 44 is suitableto serve as a welt. An outstanding featurev lof the construction is the waterproofing eiect or seal at the line of'junction between the upper and the a l outsole.

leather (this outsole may be of rubber or some other wear-resistant composition) and an upper lamina 44 of micro-porous plastic material as referred to above (Example III). The two laminae may bejoined together by means of cement I6 andthe complete sole lli'is cut to the proper size.

The lamina M of the outsole is then heated to about 80 to 90 C., by the application of infraredrays or in some other suitable manner, and the outsole 40 is laid on and pressed against the bottom of the shoe preferably with a suitable cement interposed between the outsole and the shoe bottom. A preliminary activation of the cement may be found necessary before laying and pressing the laminated outsole on the shoe bottom. The activation, inthe present example. is inherent in the process because of the heat applied for softening the plastic material and for causing it to lose its plastic memory. The bottom of the insole I0 and the upper margin 28. as

well as the outsole lamina 44, may be heated totic material is such as to soften it without closing the pores. Subsequently applied pressure, under conditions of elevated temperature as above referred to, may be such as to close the pores as will further appear.

Suiiicient pressure is used in applying the outsole to the shoe bottom to cause the porous plastic material of the lamina I4 to become compressed opposite to the margin 28 of the upper 20 and the shank piece 2B until the margin 28 is fully recessed within a recess thus formed in the lamina Il.

It will be noted in Fig. 2 that the shoe bottom cavity, as defined by the margin 28 of the upper, is a cavity the edges of which are necessarily irregular because of the lasting operation. It

v will also be noted as illustrated in the exploded view in Fig. 2 that the micro-porous plastic material fills every recess of the shoe bottom cavity The drawings show the use of an adhesive I6 and 46 in holding each of the inner land outer sole members together. It will be appreciated. however, that adhesives need not be used and that those parts as well as all other parts of the shoe assembly may be held together by stitching or other means.

A simpler construction is shown in Fig. 5. In this construction a conventional insole 50 is used the material of which is leather (it may be rubber, paper, or plastic). The shoe with an upper 52 and an insole 50 is worked into lasted relation to a last but, in this case, the marginal portion 54 of the upper 52 does not sink into the insole to any appreciable extent.

An outsole 40 such as shown in Figs. 3 and 4 is then attached `with the aid of heat and Tan adhesive to the marginal portion 54 and suiiiclent pressure is applied in sole laying to cause the margin 54 to sink into the micro-porous material of the lamina 44.

In the construction of Fig. 5, the plastic material of the outsole '40 alone is relied upon to terial of the insole as well as that of the outsole are taken advantage of in filling the bottom ll the shoe bottom cavity as bounded by the margin 54.

It will be noted that in either type of construction a well-integrated shoe bottom is'produced which assures a permanently smooth insole surface for the "foot, a water-proof seal along the shoe bottom, and serves also to provide a cushioning and generally comfortable effect for the wearer.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. In a shoe, an insole, an upper having a marginal portion overlasted thereon, a laminated sole member attached thereto and including an outsole lamina of wear-resistant material and a top lamina of synthetic resinous thermoplastic polymeric material, said polymeric material being micro-porous in a portion which extends into and fills the shoe bottom area defined by the overlasted marginal portion of said shoe upper, and said top lamina having a permanently compacted portion engaging said overlastcd portion of the shoe upper and forming a seal for said microporous portion.

s 2. A method for making a shoe which includes providing a shoe upper and inner and outer sole members, said outer sole member having a lamina of wear-resistant material for withstanding sur- 7 face wear and a top lamina of synthetic resinous thermoplasticl polymeric and micro-porous material, placing said innersole member on a last, lasting the marginal portion of the upper over said inner sole member, placing the outer sole member on the lasted shoe with the said top lamina in contact with the marginal portion of the shoe upper, and applying suillcient heat and pressure to embed the marginal portion of the shoe upper in the said polymeric material and form an integral shoe bottom structure with the polymeric material remaining micro-porous in portions extending into the shoe bottom area deilned by the said marginal portion.

3. In a shoe, inner and outer sole members, a'n upper having a marginal portion lasted over said inner sole member, each of said sole members having a lamina of synthetic resinous thermoplastic polymeric material. said polymeric material being micro-porous in portions extending into the shoe bottom area dened by the said marginal portion of said shoe upper, and the polymeric material of the outer sole member hav ing a permanently compacted portion engaging said overlasted portion of the shoe upper and forming a seal for said micro-porous portions of the inner and outer sole members.

ORVILLE N. FOUST.

REFERENCES CITED The following references are of record in the file oi this patent:

UNITED `STATES PATENTS Number Name Date V 1,197,911 Colt Sept. 12, 1916 1,400,143 Dial Dec. 13, 1921 1,579,650 Cutler Apr. 6, 1926 1,752,787 Cutler Apr. 1, 1930 1,839,984 McGhee Jan. 5, 1932 2,111,620 Gilkerson et al. Mar. 22, 1938 2,350,852 Wehr June 6, 1944 2,371,689 Gregg et al Mar. 20, 1945 2,371,868 Berg et al Mar. 20, 1945 

